I have a aeroplane in my game that is hovering above the layer. i want it to repeat going back and forth when it reach the end of the layout so I done sprite is outside layout sprite rotate - 90 degrees clockwise. All good and well but when it hover back the opposite direction it turns upside down how can i solve that and make sure it is upright.thanks

I am not quite sure what you mean, and I don't know what Behaviour you are using (Bullet?), but perhaps you could try the following action:

Event - Plane hits edge of layout-- Action - PLANE: Set Mirrored-- Action - PLANE:BULLET: Set Bullet angle of motion 0, or 180, depending on which direction you want it to go next.

If the plane is only travelling Left or Right then he can be Mirrored. You might need to disable "Set Angle" on the Object under the Bullet behaviour settings otherwise it will always set the animation to the angle of motion. If you aren't using the Bullet behaviour then Mirroring should work fine without any other adjustments.